Abstract: In a development apparatus of the present invention, a guide member is provided which extends through the toner receiving opening located above the agitation/transfer device to surround the pathway of the toner falling from the toner container to guide the same to the agitation/transfer device, the guide member is formed to be broaden toward the agitation/transfer device, and the bottom edge part of the guide member facing the agitation/transfer device is shaped to run along the rotational circumference of the agitation/transfer device, so that the piling up of toner between the agitation/transfer device and inner wall of the developing apparatus is prevented.

Abstract: In the prior developing apparatus in an image forming apparatus composed such that, the developing apparatus has an agitation/transfer means for supplying the developer while agitating the same to a developing roller for developing the latent image to be formed on a photo conductor, a toner container is mounted detachably above said agitation/transfer means, and toner is allowed to freely fall onto the same, there have happened the phenomenon that the toner piles or cakes between the inner wall of the developing apparatus and toner receiving opening or agitation/transfer means and as a result the supply of toner to the agitation/transfer means is obstructed, inducing the shortage in toner supply to the developing roller and occurrence of irregular image formation.

Abstract: The present invention relates to an image forming process and an image forming apparatus, which have a refresh means which refreshes the developing sleeve by allowing the toner on the developing sleeve to jump toward the photoreceptor drum when transfer to recording medium is not done. Refresh is performed by applying an AC bias between the photoreceptor drum and the developing sleeve. The number of dots of latent image corresponding to actual image pattern is counted and the ratio of this number of dots to the number of dots corresponding to full black original image is defined as print rate, and cumulative average print rate is calculated each time when a page or a predetermined number of pages is printed. When the average print rate falls short of proper print rate, refresh is performed. It is suitable to set several proper print rate, and the duration of application of the AC bias is varied according to the average print rate.

Abstract: A process for producing an image comprising the steps of: electrically charging a photoreceptor under dark; forming a latent image on the photoreceptor through selective imagewise exposure to light; and developing the latent image with a two-component developer comprising a carrier and a toner, the photoreceptor comprising a conductive substrate having thereon a photoconductive layer comprising amorphous silicon having a thickness of 25 .mu.m or less, the carrier is a magnetic material carrier comprising particles of a magnetic material having an average particle diameter of from 35 to 60 .mu.m, where the content of particles having a diameter of 44 .mu.m or more is 35% by weight or more. A two-component developer comprising a carrier and a toner, the carrier comprising particles of a magnetic material having an average particle diameter of from 35 to 60 .mu.m, where the content of particles having a diameter of 44 .mu.m or more is 35% by weight or more.

Abstract: To form sharp image free from flow of image or fog with an electrophotographic apparatus, which uses an a-Si photo-sensitive drum charged uniformly by having resort to the discharge phenomenon, the electrophotographic apparatus comprises an electrophotographic photo-sensitive drum having a surface layer being represented by an elementary ratio composition formula ( a-Si.sub.1-x C.sub.x :H ), x being 0.95.ltoreq..times.<1, the dynamic indentation hardness of the upper surface layer being 300 kgf/mm.sup.2 or below, the hardness of said surface layer being higher on the inner side of said photoconductive layer than on the outer surface side, preferably being gradually increasing as one goes toward the inner side of said photoelectric layer from the outer surface side, and a developing unit using a developer composed of carrier and toner particles being caused to rub the drum surface and recovered said developer in a developer vessel.

Abstract: An image forming apparatus is disclosed, in which a photo-sensitive member is exposed by exposure means accommodated therein, and development is done substantially simultaneously with the exposure.Three time elements, that is, charging time constant C, i.e., time until reaching of a predetermined charging potential on of the photo-sensitive member in a brushing contact region between the photo-sensitive member and a toner holder after the start of charging, exposure time constant R, i.e., time until the charging potential is attenuated by the exposure to a latent image potential, and development time or time T, during which the photo-sensitive member passes by the brushing contact region, are appropriately determined.